In this competitive renewal, the 3 over-arching objectives of Project #1 remain the same: a balance of genomic biomarker and biological discovery with direct clinical and translational significance. But In the last 6 years, the field of genomics has changed dramatically and we bring a whole new suite of next generation technologies to bear on these objectives for the new period of funding requested. We have also significantly expanded our scientific team to Include plasma proteomics and heart transplantation (Project #4) and a novel technology platform for multi-parameter flow cytometry genomics (Core B). Finally, we will use our new suite of genomic tools and this carefully crafted and complementary set of scientific Projects to address several new clinical challenges for kidney transplantation that have evolved In this last period: HLA-antibody desensitizafion and AMR post-transplant, the changing paradigms of chronic rejection, the pressing need to understand how current immunosuppression works and fails, the Increased risks of cardiovascular disease post-transplant and the novel hypothesis that chronic rejection and heart disease are driven by a set of common, unifying mechanisms of immunity/inflammation. Specific Aim #1: Use a new generation of genomic technologies to discover biomarker signatures and molecular pathways involved in the development, regulation and outcomes of kidney transplantation Immunity to study the evolution of immunity In 300 kidney transplant patients. Specific Aim #2: Apply whole blood, genome-wide gene expression profiling to discover gene expression-based biomarker signatures for acute and chronic antibody-mediated rejection (AMR) in 120 patients with pre-transplant HLA donor antigen-specific antibodies undergoing desensitizafion and transplantation. Specific Aim #3: Advance our mechanistic understanding of chronic kidney transplant rejection by applying the latest genomic profiling technologies detailed In Specific Aim #1. Specific Aim #4: Develop new genomic strategies to map the master molecular networks driving T and B cell activation during the development of the post-transplant immune response Including the impact of Immunosuppressive drugs on activation-Induced networks.